This new Airnef utility can download files from a WiFi-equipped Nikon camera to a computer

Airnef is a new, open-source utility for downloading/transferring images and movies from a WiFi-equipped Nikon camera to a computer. Airnef runs on Windows, Mac, and Linux. It supports all Nikon cameras that have built-in WiFi interfaces, along with those using external Nikon WU-1a and WU-1b WiFi adapters. Airnef may also work with Nikon's WT-4A and WT-5A wireless adapters for the D3/D4/D8x, although this has not been tested. Download links, installation instructions and a user guide can be found here. Here is the tutorial/demo video: